1. Field of the Disclosure
The present invention relates in general to roofing and, in particular, to a system, method and apparatus for thermal energy management in a roof.
2. Description of the Related Art
Typical residential roofs in the North America have bitumen-based roofing materials that provide satisfactory water shedding, long term durability and have aesthetic appeal. Most asphaltic roofing materials are colored in traditional dark earth tones. These colors absorb significant amounts of solar heat during hot summer times, which penetrates through the roof deck, attic and ceiling into the house. The heat penetration increases the need for cooling energy for the indoor comfort of residence occupants.
It would be advantageous to have a roofing material/system that can reduce or prevent solar heat from penetrating the roof deck into the interior of the building. It would be even more advantageous if such a system could be used with typical shingle applications without special construction requirements.
There have been asphaltic shingles with improved solar reflectance that reduce the absorption of solar heat. Although such products lower cooling energy costs, particularly in the “sunbelt” states, they are not designed for managing solar heat during night time or changing seasons. In colder climates, such products can have heating penalties due to the loss of solar heat. This is also true for the use of radiant barriers to reduce solar heat flux into the attic, which are not designed to capture the solar heat and manage it in order to maximize the energy efficiency.
Ventilated decks or ventilation systems can reduce heat flux into the attic via air flows to carry out the heat. Again, such systems are not designed for taking the advantage of solar heat and storing them for later use during the heating period. Other products use phase change material (PCM) and adsorption and desorption of moisture from desiccants to manage solar heat. However, the cost effectiveness of such systems has not been confirmed or validated. Thus, continued improvements in thermal management are desirable.